Low-speed laminar-flow high-pressure die-casting process

Abstract

The invention relates to a low-speed laminar-flow high-pressure die-casting process. The low flow gate filling speed of 0.1-6 m / s is adopted, molten metal rises horizontally at a constant speed in a flow gate and a cavity to be filled into the cavity, when the molten metal flows from the flow gate to the cavity, the flowing speed of the molten metal, close to the peripheral side of the cavity, onthe surface of a die is low, the flowing speed of the molten metal close to the middle of the cavity is high, and a streamline flowing mode that the speed is increased layer by layer from the outer layer to the inner layer is formed; and the phenomena of spraying and rolling do not occur, alloy liquid flows in the cavity and is in a laminar flow state that the whole wall thickness is evenly increased, laminar flow filling achieves the effect of avoiding gas wrapping, gas in the cavity can be sequentially exhausted from an overflow groove and an exhaust groove in the upper portion, air holes formed by flowing and gas wrapping of the alloy liquid do not exist in a casting, and the performance of the casting can be improved through high-temperature solid solution heat treatment.

Description

technical field [0001] The invention relates to the field of mechanical processing, in particular to a low-speed laminar flow high-pressure die-casting process. Background technique [0002] The traditional casting process includes high-speed and high-pressure die-casting, which is suitable for die-casting of thin-walled castings. The wall thickness of castings is more suitable when it is 3±2mm. The metal mold casting process is suitable for casting thick-walled parts. ; But it needs a larger riser feed, the riser is difficult to remove, and it is not easy to realize automation. Although squeeze casting is close to the low-speed laminar flow high-pressure die-casting process, it can cast thick-walled castings, and the wall thickness of the castings is 15±10mm. It is more suitable, and the mechanical strength of the casting is very good; but the life of the squeeze casting mold is only one-third of that of the low-speed laminar flow high-pressure die-casting mold, and a speci...

AI Technical Summary

Problems solved by technology

[0004] The current conventional die-casting process is basically turbulent flow filling, the filling speed of the ingate is 20-70m / s, and the molten metal splashes and fills the cavity at a high speed through the ingate. Outside, most of the gas is drawn into the interior of the casting by the turbulent flow, strip-shaped, and sheet-shaped high-speed sprayed alloy liquid. The produced die-casting has gas and pores inside, so it cannot be welded, nor can it be improved by solution heat treatment. The performance of castings, due to the expansion of the gas contained in the interior and surface of the castings during welding or high-temperature heat treatment, a large number of pores, air bubbles, and bubbling will be generated, and the mechanical properties will be reduced

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